The 650cc BSA Super Rocket was based on the A10 announced in October 1949, which had in turn evolved from the 495cc A7. The original rigid and plunger frames were replaced by a single top tube, duplex down tube with a swinging arm in 1954. Other improvements were a larger oil tank and chrome-panelled petrol tank. The full width front brake appeared in 1955 and the rear hub was upgraded in 1956.

There were three variants of the A10 in the late 1950s and one of them, the higher performance Road Rocket 650, became the 43bhp A10SR Super Rocket. By 1958 the 70x84mm 646 cc engine was well developed. Compression ratio was raised to 8.3:1 and the alloy cylinder head was redesigned and a hot camshaft added. The result was a BSA sports twin to rival Triumph?s Bonneville and with enough power and style to tempt the important American market.

This 1958 model is in outstanding restored condition throughout including a fully rebuilt 4-speed gearbox and engine which reputedly runs "like a Swiss watch". Both engine and frame are original to the bike from new. Sensibly uprated, it is fitted with a competition magneto and uprated twin leading shoe front brakes, though the original brakes are also available if required. Complete with its original buff log book and original registration number, this is a fast and beautiful machine which would make a fabulous addition to any collection.